Without trying to confuse you.
Domestic test is 10 for 1, 20 for 1 top up if require 20 for 2.
Great innit when you consider the varying volumes of a domestic installation
Cp12'd a place the other week with about 4 feet of gas pipe - 3 of which was 15mm.
Then we have the place i have to do the Tuppa-Cellar for whereby we maxed out (actually now the fire company have been in it could be over) the domestic criteria.
Thinking about it - NG moved the U16 meter since commissioning so it is definitely out of scope now, but you get the picture
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